Preview — Medieval Cosmology
by Pierre Duhem

Medieval Cosmology: Theories of Infinity, Place, Time, Void, and the Plurality of Worlds

These selections from Le système du monde, the classic ten-volume history of the physical sciences written by the great French physicist Pierre Duhem (1861-1916), focus on cosmology, Duhem's greatest interest. By reconsidering the work of such Arab and Christian scholars as Averroes, Avicenna, Gregory of Rimini, Albert of Saxony, Nicole Oresme, Duns Scotus, and William ofThese selections from Le système du monde, the classic ten-volume history of the physical sciences written by the great French physicist Pierre Duhem (1861-1916), focus on cosmology, Duhem's greatest interest. By reconsidering the work of such Arab and Christian scholars as Averroes, Avicenna, Gregory of Rimini, Albert of Saxony, Nicole Oresme, Duns Scotus, and William of Occam, Duhem demonstrated the sophistication of medieval science and cosmology....more

Community Reviews

a pretty good book. Mostly about ideas the medieval scholars had that were precursors to the scientific revolution of the 17th century. The developments in speculative philosophy concerning infinity, Place, the void, motion and time show that the medievals veiw of the cosmos was evolving and that the later scientific revolution wasn't as radical a change as previously thought. Nice to know what people thought about the world as they fumbled around in the dark.

The Middle Age physicists were able to formulate precise, very modern questions and offer penetratingly clear answers to questions on infinity (laying the foundations of calculus) and on the fundamentals undergirding even modern physics: place, time (and its relativity), void, and the "plurality of the worlds" (i.e., what's called "parallel universes" today).

Pierre Maurice Marie Duhem (French: [pjɛʁ moʁis maʁi dy.ɛm] was a French physicist, mathematician, historian and philosopher of science. He is best known for his work on chemical thermodynamics, for his philosophical writings on the indeterminacy of experimental criteria, and for his historical research into the science of the European Middle Ages. As a scientist, Duhem also contributed to hydrodyPierre Maurice Marie Duhem (French: [pjɛʁ moʁis maʁi dy.ɛm] was a French physicist, mathematician, historian and philosopher of science. He is best known for his work on chemical thermodynamics, for his philosophical writings on the indeterminacy of experimental criteria, and for his historical research into the science of the European Middle Ages. As a scientist, Duhem also contributed to hydrodynamics and to the theory of elasticity.

Duhem's views on the philosophy of science are explicated in his 1906 work The Aim and Structure of Physical Theory. In this work, he opposed Newton's statement that the Principia's law of universal mutual gravitation was deduced from 'phenomena', including Kepler's second and third laws. Newton's claims in this regard had already been attacked by critical proof-analyses of the German logician Leibniz and then most famously by Immanuel Kant, following Hume's logical critique of induction. But the novelty of Duhem's work was his proposal that Newton's theory of universal mutual gravity flatly contradicted Kepler's Laws of planetary motion because the interplanetary mutual gravitational perturbations caused deviations from Keplerian orbits. Since no proposition can be validly logically deduced from any it contradicts, according to Duhem, Newton must not have logically deduced his law of gravitation directly from Kepler's Laws.

Duhem's name is given to the under-determination or Duhem–Quine thesis, which holds that for any given set of observations there is an innumerable large number of explanations. It is, in essence, the same as Hume's critique of induction: all three variants point to the fact that empirical evidence cannot force the choice of a theory or its revision. Possible alternatives to induction are Duhem's instrumentalism and Popper's thesis that we learn from falsification.

As popular as the Duhem–Quine thesis may be in the philosophy of science, in reality, Pierre Duhem and Willard Van Orman Quine stated very different theses. Pierre Duhem believed that experimental theory in physics is fundamentally different from fields like physiology and certain branches of chemistry. Also, Duhem's conception of the theoretical group has its limits, since not all concepts are connected to each other logically. He did not include at all a priori disciplines such as logic and mathematics within these theoretical groups in physics which can be tested experimentally. Quine, on the other hand, conceived this theoretical group as a unit of a whole human knowledge. To Quine, even mathematics and logic must be revised in light of recalcitrant experience, a thesis that Duhem never held.

A quote of Duhem on physics:

A theory of physics is not an explanation. It is a system of mathematical propositions, deduced from a small number of principles, which have for their aim to represent as simply, as completely and as exactly as possible, a group of experimental laws....more